Machines used in earth moving, mining, construction, forestry, or similar applications have an upper frame rotatably mounted to a lower frame. The lower frame of such a machine often includes a track assembly, which has a track on a left side and a track on a right side of the machine. An operator of the machine can independently control the left and right tracks, which cooperate to propel the machine in a desired direction. To propel the machine in the forward direction, the operator may use a right travel pedal to actuate the right track and a left travel pedal to actuate the left track. Specifically, the operator can use the right travel pedal to speed up or slow down the right track, and similarly use the left travel pedal to speed up or slow down the left track.
The operator can rotate the upper frame by 180° or more while maintaining the lower frame in its original position. In this configuration, the right track is located on the operator's left side and the left track is located on the right side of the operator. When the operator pushes on either of the pedals, an act intuitively associated with moving forward, the machine actually travels in the reverse direction. Operating the machine in this situation may become counter-intuitive and may pose mental strain on the operator.
One way to overcome this problem consists of rotating the lower frame of the machine without altering the relative positions of the upper and lower frame, effectively turning the whole machine around. In certain applications, however, geographic and/or space constraints may prevent the operator from turning the machine around. For example, in swamp logging operations, turning the whole machine can tear and damage the underlying surface due to the inherent instability of the terrain. In other situations, narrow and/or restricted workspaces may constrain the machine allowing it only to move in a forward or rearward direction.
One attempt to address some of the problems described above is disclosed in United States Patent Application Publication No. U.S. 2008/0119985 of Schubitzke that published on May 22, 2008 (“the '985 publication”). In particular, the '985 publication discloses a control system for a rotating turret vehicle having steering controls in the turret, wherein the steering controls may be reversed when the turret faces the rear of the vehicle. The disclosed system of the '985 publication uses directional valves and valve matrices to reroute the hydraulic fluids from one side of the vehicle to the other in order to reverse the steering controls.
Although the '985 publication discloses a system for reversing the steering controls based on a turret position, the system of the '985 publication may still be problematic. For example, the disclosed system uses directional valves and valve matrices to route the hydraulic fluids. This configuration may involve increased cost of implementation and operation and longer reaction times due to the complexities of hydraulic fluid switching.
The control system for switching traction device inputs of the present disclosure solves one or more of the problems set forth above and/or other problems in the art.